The cleaning performance of washing or cleaning agents is improved by adding further components, which can be summarized under the heading “washing auxiliaries”, in addition to the surfactants and builder materials indispensable for the washing process. Washing auxiliaries include for example foam regulators, graying inhibitors, bleaching agents, bleach activators and dye transfer inhibitors. Further washing auxiliaries are substances which impart soil-repelling properties to the laundry fibers and which, if present during the washing process, assist the soil detachment capacity of the other components of the washing agent. Such substances with a soil detachment capacity are often known as “soil release” active substances or, due to their capacity to provide a soil-repelling finish on the treated surface, for example fabric, as “soil repellents”.
Soil release active substances known in the prior art are polyesters which contain dicarboxylic acid units, alkylene glycol units and polyalkylene glycol units. In particular, polyesters of phthalic acid and/or terephthalic acid or of the derivatives thereof, in particular polyesters prepared from ethylene terephthalates and/or polyethylene glycol terephthalates and/or polypropylene glycol terephthalates or anionically and/or nonionically modified derivatives of these are used in washing or cleaning agents.
Due to their chemical similarity to polyester fibers, these polyesters display particularly good soil detachment action on polyester-containing textile fabrics.
WO 96/16150 discloses that the cleaning performance of washing or cleaning agents can be increased by interaction of polymers with a soil detachment capacity with a surfactant combination prepared from ether sulfate and alkyl oligoethoxylates.
A requirement still, however, remains to improve the cleaning performance of washing or cleaning agents comprising a polymer with a soil detachment capacity.